Merge tag 'nfs-for-3.4-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

Pull NFS client updates for Linux 3.4 from Trond Myklebust:
 "New features include:
   - Add NFS client support for containers.

     This should enable most of the necessary functionality, including
     lockd support, and support for rpc.statd, NFSv4 idmapper and
     RPCSEC_GSS upcalls into the correct network namespace from which
     the mount system call was issued.

   - NFSv4 idmapper scalability improvements

     Base the idmapper cache on the keyring interface to allow
     concurrent access to idmapper entries.  Start the process of
     migrating users from the single-threaded daemon-based approach to
     the multi-threaded request-key based approach.

   - NFSv4.1 implementation id.

     Allows the NFSv4.1 client and server to mutually identify each
     other for logging and debugging purposes.

   - Support the 'vers=4.1' mount option for mounting NFSv4.1 instead of
     having to use the more counterintuitive 'vers=4,minorversion=1'.

   - SUNRPC tracepoints.

     Start the process of adding tracepoints in order to improve
     debugging of the RPC layer.

   - pNFS object layout support for autologin.

  Important bugfixes include:

   - Fix a bug in rpc_wake_up/rpc_wake_up_status that caused them to
     fail to wake up all tasks when applied to priority waitqueues.

   - Ensure that we handle read delegations correctly, when we try to
     truncate a file.

   - A number of fixes for NFSv4 state manager loops (mostly to do with
     delegation recovery)."

* tag 'nfs-for-3.4-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (224 commits)
  NFS: fix sb->s_id in nfs debug prints
  xprtrdma: Remove assumption that each segment is <= PAGE_SIZE
  xprtrdma: The transport should not bug-check when a dup reply is received
  pnfs-obj: autologin: Add support for protocol autologin
  NFS: Remove nfs4_setup_sequence from generic rename code
  NFS: Remove nfs4_setup_sequence from generic unlink code
  NFS: Remove nfs4_setup_sequence from generic read code
  NFS: Remove nfs4_setup_sequence from generic write code
  NFS: Fix more NFS debug related build warnings
  SUNRPC/LOCKD: Fix build warnings when CONFIG_SUNRPC_DEBUG is undefined
  nfs: non void functions must return a value
  SUNRPC: Kill compiler warning when RPC_DEBUG is unset
  SUNRPC/NFS: Add Kbuild dependencies for NFS_DEBUG/RPC_DEBUG
  NFS: Use cond_resched_lock() to reduce latencies in the commit scans
  NFSv4: It is not safe to dereference lsp->ls_state in release_lockowner
  NFS: ncommit count is being double decremented
  SUNRPC: We must not use list_for_each_entry_safe() in rpc_wake_up()
  Try using machine credentials for RENEW calls
  NFSv4.1: Fix a few issues in filelayout_commit_pagelist
  NFSv4.1: Clean ups and bugfixes for the pNFS read/writeback/commit code
  ...

1 files changed, 20 insertions, 7 deletions

diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 32aa6917265a..4aaf0316d76a 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -207,7 +207,7 @@ struct nfs_cache_array_entry {
 };
 
 struct nfs_cache_array {
-        unsigned int size;
+        int size;
         int eof_index;
         u64 last_cookie;
         struct nfs_cache_array_entry array[0];
@@ -1429,6 +1429,7 @@ static struct dentry *nfs_atomic_lookup(struct inode *dir, struct dentry *dentry
         }
 
         open_flags = nd->intent.open.flags;
+        attr.ia_valid = 0;
 
         ctx = create_nfs_open_context(dentry, open_flags);
         res = ERR_CAST(ctx);
@@ -1437,11 +1438,14 @@ static struct dentry *nfs_atomic_lookup(struct inode *dir, struct dentry *dentry
 
         if (nd->flags & LOOKUP_CREATE) {
                 attr.ia_mode = nd->intent.open.create_mode;
-                attr.ia_valid = ATTR_MODE;
+                attr.ia_valid |= ATTR_MODE;
                 attr.ia_mode &= ~current_umask();
-        } else {
+        } else
                 open_flags &= ~(O_EXCL | O_CREAT);
-                attr.ia_valid = 0;
+
+        if (open_flags & O_TRUNC) {
+                attr.ia_valid |= ATTR_SIZE;
+                attr.ia_size = 0;
         }
 
         /* Open the file on the server */
@@ -1495,6 +1499,7 @@ static int nfs_open_revalidate(struct dentry *dentry, struct nameidata *nd)
         struct inode *inode;
         struct inode *dir;
         struct nfs_open_context *ctx;
+        struct iattr attr;
         int openflags, ret = 0;
 
         if (nd->flags & LOOKUP_RCU)
@@ -1523,19 +1528,27 @@ static int nfs_open_revalidate(struct dentry *dentry, struct nameidata *nd)
         /* We cannot do exclusive creation on a positive dentry */
         if ((openflags & (O_CREAT|O_EXCL)) == (O_CREAT|O_EXCL))
                 goto no_open_dput;
-        /* We can't create new files, or truncate existing ones here */
-        openflags &= ~(O_CREAT|O_EXCL|O_TRUNC);
+        /* We can't create new files here */
+        openflags &= ~(O_CREAT|O_EXCL);
 
         ctx = create_nfs_open_context(dentry, openflags);
         ret = PTR_ERR(ctx);
         if (IS_ERR(ctx))
                 goto out;
+
+        attr.ia_valid = 0;
+        if (openflags & O_TRUNC) {
+                attr.ia_valid |= ATTR_SIZE;
+                attr.ia_size = 0;
+                nfs_wb_all(inode);
+        }
+
         /*
          * Note: we're not holding inode->i_mutex and so may be racing with
          * operations that change the directory. We therefore save the
          * change attribute *before* we do the RPC call.
          */
-        inode = NFS_PROTO(dir)->open_context(dir, ctx, openflags, NULL);
+        inode = NFS_PROTO(dir)->open_context(dir, ctx, openflags, &attr);
         if (IS_ERR(inode)) {
                 ret = PTR_ERR(inode);
                 switch (ret) {